JP2649209B2 - Method for manufacturing thin-film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin-film magnetic head used in, for example, a magnetic disk drive and other magnetic recording / reproducing devices.

[0002]

2. Description of the Related Art Conventionally, thin-film magnetic heads have been employed in order to improve recording density and information transfer speed with the performance enhancement of magnetic disk devices. In general, a thin-film magnetic head is manufactured by using a deposition technique such as electroplating or sputtering, and a fine processing technique by photolithography.

FIGS. 5 and 6 schematically show the structure of a conventionally known in-plane recording / reproducing thin film magnetic head. Al ₂ O ₃ in -TiC based substrate 1 made of a ceramic material or the like, an insulating film 2 such as alumina is deposited, and the lower magnetic film 3 is formed constituting the lower magnetic pole thereon. A gap film 4 made of alumina or the like is formed on the lower magnetic film 3.
Are formed thereon, and insulating films 5, 6, 7, made of an organic insulating resin material such as a novolak resin, spiral conductive coils 8, 9 made of Cu or the like, and an upper magnetic film 10 are sequentially laminated. Further, a protective film 11 of alumina or the like is formed on the upper magnetic film 10 by sputtering or the like. The thin-film magnetic head element thus formed is cut out from the substrate, mounted on individual sliders, and used as a thin-film magnetic head.

[0004]

According to the prior art, the insulating film is usually formed by applying, for example, a novolak resin, soft-baking, applying a photomask, exposing, developing, heat-treating and curing. It is formed. Since the novolak resin has fluidity due to heat and shrinks by baking, the first insulating film 5 is formed by a step between the lower magnetic film 3 and the substrate 1, especially the lower magnetic film, as shown in FIG. The thickness near the edge of No. 3 becomes very thin. FIG.
The relationship between the distance D between the upper end of the lower magnetic film 3 where the thickness of the insulating film 5 is the smallest and the conductor coil 8 and the withstand voltage of the insulating film is shown in a diagram based on experimental results. From the figure,
In this experiment, it is easily understood that when the distance D becomes 1 μm or less, the withstand voltage sharply decreases. As described above, when the first conductor coil 8 formed on the first insulating film 5 and the lower magnetic film 3 are too close to each other at the edge portion, sufficient insulation is not maintained and the gap between the magnetic pole coils is not maintained. There is a problem that the insulation resistance and the dielectric breakdown voltage are reduced, and there is a possibility that recording and reproduction of information by the thin film head may not be performed normally.

If the entire first insulating film 5 is made thicker, the thickness of the first insulating film 5 near the periphery of the lower magnetic film 3 can be sufficiently ensured. Since the angle becomes very steep, the internal stress of the protective layer 11 formed thereon increases, cracks and the like may occur, and there is a possibility that the reliability may be reduced.

Therefore, a method of manufacturing a thin film magnetic head according to the first aspect of the present invention has been made in view of the above-mentioned problems of the prior art. Even at the edge of the magnetic film formed thereon, the thickness of the insulating film formed thereon is sufficiently ensured without causing cracks or the like in the protective layer, and the magnetic film and the conductor coil are formed. It is an object of the present invention to provide a method of manufacturing a thin-film magnetic head that can ensure good insulation between the thin film and a film, increase the dielectric breakdown voltage, and improve the reliability.

[0007]

According to the present invention, there is provided a method of manufacturing a thin-film magnetic head according to the present invention, comprising: a magnetic film formed on a substrate;
A method of manufacturing a thin-film magnetic head having a magnetic circuit comprising a conductor coil film formed thereon with an insulating film interposed therebetween , comprising:
Forming a narrow band-shaped resin insulating layer on the portion where the coil film is formed, and then forming an insulating film thereon so as to include the narrow band-shaped resin insulating layer and the magnetic film. It is characterized by.

[0008]

According to the method of manufacturing a thin-film magnetic head according to the first aspect, by providing a narrow band-shaped resin insulating layer around the magnetic film, the outer shape and dimensions of the magnetic film are slightly increased in appearance. Can be. As a result, the position of the edge portion of the magnetic film shifts outward by the width of the band-shaped resin insulating layer. Therefore, when the insulating film is formed thereon, the thickness of the insulating film becomes In this example, the thickness of the magnetic film becomes smaller as before due to the step between the substrate and the substrate, but at the edge of the magnetic film on the inner side, a thickness is obtained that can secure sufficient electrical insulation between the conductor coil film. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described using embodiments with reference to the accompanying drawings.

First, a method of manufacturing a thin-film magnetic head for in-plane recording / reproduction according to the present invention will be described with reference to FIGS.
Similarly to the above-described conventional technique, a lower magnetic film 3 made of a soft magnetic material such as a Ni—Fe alloy or a cobalt alloy is formed on a substrate 1 on which an insulating film 2 such as alumina is deposited by lithography and electroplating. The pattern is formed by an ordinary method such as sputtering, etching and the like. Although not shown, a gap film 4 made of alumina or the like is formed on the substrate 1 including the lower magnetic film 3 by sputtering. In this state, as shown in FIG. 1-A, a narrow insulating layer 12 made of an organic insulating resin material such as a novolak resin is slightly covered along the periphery of the lower magnetic film 3 at its edge. Apply in a band. As shown in FIG. 2, the insulating layer 12 has at least a portion of the conductor coils 8 and 9 except for the tip of the lower magnetic film 3 constituting the lower magnetic pole.
May be provided in a region where is formed.

Next, when the organic insulating layer 12 is soft-baked, the novolak resin also has fluidity due to heating, and as shown in FIG. The insulating layer 12 is formed. On the insulating layer 12 and the lower magnetic film 3 thus formed,
As in the conventional case, an organic insulating resin such as a novolak resin is applied (FIG. 1-C) and heat-treated to form an insulating film 5 (FIG. 1-D). Next, as shown in FIG.
The conductor coil 8 is patterned on the above by a usual method. Insulating film 5, by becomes thinner portion near the insulating layer 12, the insulating layer 12 is present by the heat treatment, the lower
The edge position of the magnetic film 3 is shifted outward by the width of the insulating layer 12.
As a result, sufficient insulation between the conductor coil 8 and the lower magnetic film 3 is ensured even in the peripheral portion. Further, on the conductor coil 8, the interlayer insulating films 6, 7, the second conductor coil 9, and the upper magnetic film 10 are laminated, and the protective layer 11 is formed to complete the thin-film magnetic head.

Next, another embodiment of the present invention will be described with reference to FIGS. In this embodiment, as shown in FIGS. 3A and 4, a narrow band-shaped insulating layer 13 such as a novolak resin is provided around the lower magnetic film 3 with a small gap. At this time, the insulating layer 13 has substantially the same height as the lower magnetic film 3, but the height after the heat treatment is too low compared to the lower magnetic film 3, and the insulating film 5 is formed thereon. The lower magnetic film 3 may be used as long as sufficient insulation is not ensured.

The insulating layer 13 is soft-baked as in the first embodiment. Although a slight gap is provided between the insulating layer 13 and the lower magnetic film 3 as described above, since the novolak resin has fluidity by heating, the insulating film 13 As shown, it is formed so as to sufficiently contact the end face of the lower magnetic film 3. Next, as shown in FIGS. 3C to 3E, the insulating layer 5 and the conductor coil 8 are sequentially formed on these. In the case of the second embodiment, since the insulating layer 13 is smaller than the insulating layer 12 of the first embodiment, the insulating film becomes thinner near the edge of the lower magnetic film 3. 3 and the conductor coil 8 are separated to such an extent that sufficient insulation can be maintained.

As can be seen from the first and second embodiments, in the present invention, the insulating layers 12 and 13 are provided so as to overlap the peripheral edge of the lower magnetic film 3 or to have a gap. In the same manner, a desired effect can be obtained.
Therefore, the insulating layer does not need to be disposed more accurately than necessary with respect to the lower magnetic film, and can be formed relatively easily.

The present invention is not limited to the above embodiment, but can be implemented with various modifications and changes within the technical scope thereof. For example, the above embodiment relates to a method for manufacturing a thin-film magnetic head for in-plane recording / reproducing, but can be similarly applied to a method for perpendicular recording / reproducing. Although the insulating layers 12 and 13 are provided all around the lower magnetic film 3 except for the front end portion, the same effect can be obtained by providing the insulating layers 12 and 13 only along both sides of the lower magnetic film. In addition, novolak resin was used as an insulating material,
It goes without saying that various other organic insulating resin materials can be used.

[0016]

Since the present invention is configured as described above, it has the following effects.

According to the method of manufacturing a thin film magnetic head according to the first aspect, at least the conductor coil film around the magnetic film is shaped.
By providing a narrow band-shaped resin insulation layer in the part to be formed
The external dimensions and dimensions of the magnetic film
In, despite the difference in level between the substrate and the magnetic film, clad in protective film
It is possible to form an insulating film having a sufficient thickness even at the edge portion of the magnetic film without generating a crack or the like ,
As a result , the distance between the conductor coil film and the magnetic film is sufficiently ensured, and good insulation between them can be ensured. The insulation resistance between the magnetic pole coils is increased, and the reliability of the dielectric breakdown voltage is high. Can be provided. In addition, the narrow strip-shaped resin insulation layer
High accuracy is not required for alignment and film thickness
Can be formed by a relatively simple process,
Performance can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a process of forming an insulating layer according to a first embodiment of the present invention, comprising FIGS.

FIG. 2 is a plan view of FIG. 1-A.

3A to 3E are diagrams illustrating a process of forming an insulating layer according to a second embodiment of the present invention.

FIG. 4 is a plan view of FIG. 3-A.

FIG. 5 is a schematic perspective view showing the structure of a conventional thin film magnetic head.

6 is a longitudinal sectional view of the thin-film magnetic head shown in FIG.

FIG. 7 is a sectional view taken along line VII-VII in FIG. 5;

FIG. 8 is a diagram showing a relationship between a distance D between an upper end of a lower magnetic film and a conductor coil and a withstand voltage of an insulating film.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Insulating film 3 Lower magnetic film 4 Gap film 5, 6, 7 Insulating film 8, 9 Conductor coil 10 Upper magnetic film 11 Protective layer 12, 13 Insulating layer

Claims (1)

(57) [Claims] 1. A method for manufacturing a thin-film magnetic head having a magnetic circuit comprising a magnetic film formed on a substrate and a conductor coil film formed thereon with an insulating film interposed therebetween, the method comprising: At least along the periphery of the magnetic film ,
In the portion where the conductor coil film is formed, a narrow band-shaped resin
A step of forming an insulating layer, and a step of forming the insulating film on the narrow band-shaped resin insulating layer so as to include the resin insulating layer and the magnetic film. Head manufacturing method.